I don't discount their greediness and wanting free stuff. Definitely a thing. However, almost every sibling of a disabled child I've spoken to has gone through this grind with their parents to get them to pay for anything. The money flows much more freely for the disabled child. I knew growing up that it wasn't enough to ask for something. I had to campaign for it. Stuff that other kids hated (music lessons, dance classes, soccer), I wanted to do because it gave me a life outside of our house.
My Mom says now that she's sorry. I was just never her priority. And I'm grateful she's stopped pretending it wasn't that way.
I understand the viewpoint that I has not had a job. He hasn't had a steady part time job like some kids. I didn't either. I helped out around the house, helped with the family business, ran errands once I could drive, etc. On top of that, I was a caregiver. A part time job would have been easier. And just try getting homework done in that level of chaos. I went to the library after school because there was never any way of knowing what I was going home to. It was exhausting.